"Writing Essays and Term papers" -- Ch. 7 in A Short Guide to Writing About Biology, 5th ed., by Jan Pechenik.
Examples of how to list your references:
Journal article:
Perna, N. T., G. Plunkett III, V. Burland, B. Mau, J. D. Glasner, et al. 2001. Genome sequence of enterohaemorrhagic Escherichia coli O157:H7. Nature409: 529-533.
(Note that if there are more than six authors, you may list the first five and "et al.")
Web site:
Web site references should include the author, the date of posting, the title of the page or article, the organization, the URL, and the date accessed, as in this example:
The Institute for Genome Research. 1999-2002. "Escherichia coli O157:H7 VT2-Sakai." http://www.tigr.org/tigr-scripts/CMR2/GenomePage3.spl?database=ntec03 (7 February 2004).
(Here no author was given, so the organization is listed in the author spot. If no date is given, list the date accessed in the date spot.)
Book:
Salyers, A. A., and D. D. Whitt. 2002. Bacterial Pathogenesis: a Molecular Approach, 2nd ed. ASM Press, Washington, DC.
(Note that title is italicized. Underlining is a holdover from the days of typewriters.")
Chapter in a book:
Muñoz-Elías, E. J., and J. D. McKinney. 2002. Bacterial persistence: strategies for survival, Ch. 23 In S. H. E. Kauffman, A. Sher, and R. Ahmed, eds. Immunology of Infectious Diseases. ASM Press, Washington, DC.
Revising your paper:
"Revising" -- Ch. 5 in A Short Guide to Writing About Biology, 5th ed., by Jan Pechenik.